Shortages of the staple crop of half the world’s people could bring unrest across Asia and Africa, reports foreign affairs editor Peter Beaumont

A global rice shortage that has seen prices of one of the world’s most important staple foods increase by 50 per cent in the past two weeks alone is triggering an international crisis, with countries banning export and threatening serious punishment for hoarders.

With rice stocks at their lowest for 30 years, prices of the grain rose more than 10 per cent on Friday to record highs and are expected to soar further in the coming months. Already China, India, Egypt, Vietnam and Cambodia have imposed tariffs or export bans, as it has become clear that world production of rice this year will decline in real terms by 3.5 per cent. The impact will be felt most keenly by the world’s poorest populations, who have become increasingly dependent on the crop as the prices of other grains have become too costly.